hdu 4568 Hunter (旅行商问题)

HunterTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 692    Accepted Submission(s): 190

Problem DescriptionInputOutputSample InputSample OutputSource#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>#include <cmath>#include <string>#include <map>#include <stack>#include <vector>#include <set>#include <queue>//#pragma comment (linker,"/STACK:102400000,102400000")#define maxn 205#define MAXN 100005#define mod 1000000000#define INF 0x3f3f3f3fusing namespace std;int n,m,ans,k,cnt,est;int dp[1<<14][14];int u[14],v[14];int id[maxn][maxn],dist[14][14];bool vis[maxn][maxn];int mp[maxn][maxn];int dx[]={-1,1,0,0};int dy[]={0,0,-1,1};struct Node{ int x,y,step; bool operator <(const Node&x1) const { return step>x1.step; }}cur,now;priority_queue<Node>q;void bfs(int bx,int by,int xx){ int i,j,nx,ny,tx,ty,flag=0; memset(vis,0,sizeof(vis)); while(!q.empty()) q.pop(); cur.x=bx; cur.y=by; cur.step=0; vis[bx][by]=1; q.push(cur); while(!q.empty()) { now=q.top(); q.pop(); nx=now.x; ny=now.y; if(id[nx][ny]!=-1) dist[xx][id[nx][ny]]=now.step; for(i=0;i<4;i++) { tx=nx+dx[i]; ty=ny+dy[i]; if(tx<1||tx>n||ty<1||ty>m) { if(!flag) flag=1,dp[1<<xx][xx]=now.step+mp[u[xx]][v[xx]]; continue ; } if(vis[tx][ty]||mp[tx][ty]==-1) continue ; cur.x=tx; cur.y=ty; cur.step=now.step+mp[tx][ty]; vis[tx][ty]=1; q.push(cur); } }}void solve(){ int i,j,p,ma,st; ma=1<<k; for(i=0;i<ma;i++) { for(j=0;j<k;j++) { if(dp[i][j]>=INF) continue ; for(p=0;p<k;p++) { if(p==j||(i&(1<<p))) continue ; st=i|(1<<p); dp[st][p]=min(dp[st][p],dp[i][j]+dist[j][p]); } } } ans=INF; for(i=0;i<k;i++) { ans=min(ans,dp[est][i]+dp[1<<i][i]-mp[u[i]][v[i]]); } if(ans>=INF) ans=0;}int main(){ int i,j,t; scanf("%d",&t); while(t--) { scanf("%d%d",&n,&m); for(i=1;i<=n;i++) { for(j=1;j<=m;j++) { scanf("%d",&mp[i][j]); } } memset(id,-1,sizeof(id)); memset(dp,0x3f,sizeof(dp)); scanf("%d",&k); for(i=0;i<k;i++) { scanf("%d%d",&u[i],&v[i]); u[i]++,v[i]++; id[u[i]][v[i]]=i; } est=(1<<k)-1; for(i=0;i<k;i++) { if(mp[u[i]][v[i]]==-1) // 汗 去掉也能A { est=est&(~(1<<i)); continue ; } bfs(u[i],v[i],i); if(dp[1<<i][i]==INF) est=est&(~(1<<i)); // 汗 去掉也能A 没有设track } solve(); printf("%d\n",ans); } return 0;}